Rock drill mechanism



2 Sheets-Sheet l nocx DRILL MECHANISM Filed July 30, 19:57

W. A. MORRISON mvENToR wallzamilMolwsm- HIS ATILORNEY;

July 26, 1938.

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I ROCKVDRILL mz cxmusu Filed July 50, 19:57 2 sheets-s eet 2 INVENTOR mm ammm BY HIS ATTORNEY.

Patented July 26, 1938 UNITED "STATES PATENT OFFICE ROCK lmu rfionA lsm I 1 William A. Morrison,

Easton, Pa, assignor to I Ingersoll-Rand Company,

Jersey City, N. J., a

corporation of New Jersey Application July 30, 1937, Serial No. 156,436

6 Claims.

respect to the working implement which the hammer piston actuates.

Another object of the invention is to utilize the force of the hammer piston of a rock drill for actuating both the rotation mechanism and the feeding mechanism.

Still another object is to use an element or elements of the rotation mechanism for transmitting the force of the hammer piston to the feeding mechanism.

Further objects will be in part obvious and in part pointed out hereinafter.

In the drawings accompanying this specification and in which similar reference numerals refer to similar parts,

Figure 1 is a longitudinal view, partly in section, of a rock drilling mechanism constructed in accordance with the practice of the invention,

Figure 2 is a view similar to Figure 1 showing a detailed view of the elements employed for transmitting power from the hammer piston to the feeding mechanism, 7

Figures 3, 4, 5 and 6 are transverse views taken through Figure 1 on the lines 3-3, 4--4, 5-5 and 6-6, respectively, and

Figure 7 is a plan view, in section, taken through Figure 6 on the line 1-1.

Referring more particularly to the drawings; rock drilling mechanism com-.

20 designates a prising a rock drill 2| and a shell 22 to guide the rock drill and accordingly having a pair of guideways 23 to slidably receive ribs 24 carried by the casing parts of the rock drill 2|.

The rock drill 2| comprises the usual cylinder 25 having a piston chamber 26' to accommodate a reciprocatory hammer piston 21 which controls a free exhaust port 28. The hammer piston has a reduced stem 29 to deliver blows against a working implement, as for example a drill steel (not shown), but the end of which may extend into the front casing part or front head 30 arranged at the forward end of the cylinder 25.

The front head 30 and the cylinder 25 are separated by a bosses on its ends extending into the adjacent ends of the front head and'the cylinder and also having a bore 32 to guide the stem 29. The front head 30 houses suitable chuck mechanism 33 having ribs 34 which are slidably engaged by ribs 35 extending longitudinally of the piston stem 29 to prevent relative rotary movement between the piston 21 and the chuck 33;.

' implement to cause the front cylinder washer 3| having The chuck mechanism 33 may be of any well known type adapted to interlockingly engage the working implement sothat upon the impartation of the rotary movement to the chuck 33 the working implement will alsoto rotate its cutting end to new positions between blows. of the hammer piston 21. A well known example of such chuck mechanism is that generally known as the fLeyner type in which the chuck interlocks with lugs on the working two to rotate in unison and the working implement is capable of a lim-- ited degree of reciprocatory movement relatively to the chuck.

In the rearward end of the cylinder 25 is an enlarged recess 36 to accommodate valve mechanism 31 of which only the chest is shown. The valve mechanism may be of any well known type and the rock drill may be provided with the usual ports and passages (not shown) controlled by the valve mechanism to distribute pressure fluid to the ends of the piston chamber foractuating the piston 21.

The valve mechanism is held against rotary movement with respect to the cylinder 25 by a key 38 engaging these elements and is held against endwise movement by a plate 39 overlying the rear end of the cylinder 25. The plate 39, moreover, serves as a seat for a back head 40 whichconstitut'es-the rearmost casing part of the rock drill and is securedtd the cylinder by the usual side rods 4| arranged on opposite sides of the rock drill.

The rock drill is provided with suitable means for imparting rotary movement to the piston 21 and thus to the chuck mechanism interlocked therewith. That illustrated and designated 42 is in the form of a bar extending through the plate 39 and the valve mechanism 31 into the piston 21, and the portion of the bar lying within the piston is provided with spiral ribs 43 to interlockingly engage similar ribs (not shown) in a nut 44 threaded into the piston 21.

On the rearward end of .the' bar is a head 45 which carries a series of pawls 46 of conventional type having trunnions 41 seated in the head 45 to serve as pivots for the pawls. The wing portions 48 of the pawls lie in recesses 49 in the periphery of the head 45 and are urged outwardly by spring-pressed plungers 50 slidable in the head 45.

The head 45 is arranged in a recess 5| in the back head 40 andis encircled by a. ratchet ring 52 which, in accordance with the practice of the invention, is rotatable within the recess and has a smooth cylindrical bearing portion 53 that seats upon the wall of the recess 5|. The teeth 54 of the ratchet ring, and which the pawls 40 are intended to engage, are located on and extend'along the entire inner surface of the ratchet tween the bar 42 and the ratchetring52.

. ring. Their side surfaces, as is customary, serve as seats for the ends of the pawls 46 to prevent relative rotary movement in onedirection be- S uitable means are provided to enable the direction of rota'tionof the ratchet ring 42 tobe selectively controlledflTo this end a block '55- the ratchet ring, rearwardly' of the is disposed in head 45, to provide bearings forjtwo sets of spring-pressed pawls 56 and 51' of which 'the pawls designated 56 are arranged to engageone side ofv the ratchetteethJ54 and the pawl or pawls 51 is positioned to act as abutments for the opposite sides of the teeth 54. Preferably, a

plate I5 is interposed between the head-l5 and the block toretain the pawls intheir respective carriers, a: s V v s p The block 55 maybe held flxedlyin position in any suitable -manner,. as, for example, by

seating astem IQ of theblock55 in iaybore l8 in the back head and firmly securing the stemv l9 to the back head 40 with a key l7 extending transverselyof the back headand ngaging-ja notch 16 in the peripheryofr the sftemlli 1 Means are provided-for controlling engage ,ment of the pawls 56 and 5'! with the teeth 54.

' v To this end a plate 58;is arranged'rotatably-jin theback head rearwardly of plate carries a pair of- Wings 59 w i h overlie wardly of theblock 55. The manipulation' of the plate 58-, engage'the free ring rotary movement ofthe plate. trated comprises a shaft arranged the block 55.. The

:51 extending rearwings 59 will; upon portionsof the pawls 56 and ends of the pawls and rock them out of'the path of movement of the teeth 54. 7

Any suitable meansmay be pro ided for eifect- That illusinthezback head '40 and having anVeccentricpin-BI which 'extendsinto'a slot 62 in therearmost'endof the plate 58, preferably near the periphery thereof. The shaft 69 extends exteriorly of the back head and carries a lever 63 whereby-it may be manipulated. V 1 I V V In order that therplate 58 may be heldfixedly .injeither of its limitingposition's, that is; in the positions 'in' which itholds the ipawls .56, or that "designated-51,l inr'disengaging position, the plate 58 is provided in its rearward end with depressions 64, of;which'o n1y one'is shown; to receive the end-of a spring pressed plunger arranged in the. back head 40.7 p As hasobeen previously stated. the ratchet ring 52 is'rotatable in the recess 5|, 7 ment of the .ratchetring is employed in the 'form of theinvention illustrated; for imparting and this move;-

feedingm'ovement to the rock drill for actuating it alongfthe shell22- in orderto maintain the percussive element of the rock drill in a :favor able position with respect'to the working implement. The ratchet ring is accordingly provided with gear teeth 66 on its periphery to mesh with an idler pinion 51-journalled in the back'head I and meshing with 1teeth 68 44 and the'plate 39 V in the periphery of a feed-nut 69 rotatabler'in a bore 10 located, in the present instance,fin lugs H and" on the back head and the plate 39'."

The lugs, "H and 12 extend into the .-'shell22 and the bore 191's coaxial with'a feed screw 13 extending longitudinally of the shell 22. The feed screw is supported at its ends'bysuitable bearings of' which only one; designated 14, is

7 shown at the rearward end of theshell to which it may be suitably locked by a key 15; 1 V The threads 16 of thefeed nut are of nonlocking pitch and extend fromone end "to; the

feed screw upon which ed. Preferably plates '11 aredisposed at the ends to protect the lugs H" and l2 against the eifects of wear incident to the movement of the feed nut.

sion into therock drill is 1 sage 8! extending through flushing the hole is held fixedly in position into the rear end of the back head and seating 7 against the adjacentend' of the water tube. A passage in the back head affords communicaand a supplyconby its act of 'reversalimparts a :the rock drill the feed other of the feed nut to assure an ample area of engagement between them and those of the the feed nut 69 is threadof the feed nut 69 I 'The pressure fluid-employed for actuating the piston may be conveyed to the rock drill through a suitable conduit (not/shown) and its admis-' controlled by a throttle valve 18 arranged in the back head 44. The

throttle valve is shown as being of the rotary be in constant communication with the source of pressure fluid supply,

tion between the chamberglB and a supply'pas the'plate 39 and opening into a supplyreservoir 82' in the end of the plate 39 adjacent the-valve mechanism 31.

type having a central chamber 79 which may and a port 89in -the 'wall 'of the throttle valve affords communicathe back; head 40and -20 The rock drill is, moreover, provided withla" waterztube 8 3 which extends through the back head and the percussive element to convey cleansing water to the working implement for being drilled. The water tube tion between the watertube nection 86' attached to the back head.

by a plug B4threaded The operation of the device'is as follows: i

it be'assumed that the rock drill 20 is in; operdeliver blows to the pies a position in which'a pawl '51 out'of the path of therratchet teeth 54 unimpededto strike: against the working implement,;it being understood, of course; that the the} ratchet ring and the pawls 46 willmerely pass over the crests of theteeth '54. l'I'hepawls 41- 'bar 42 will then rotate freely with respectto.

5150' will, however, bexin constantreadinessL'for engagement with the teeth 54,as will also be the pawls .56.; Thus, when thepiston 21. reverses in the front end of the piston chamber 25and ings, and thereby enable the rock drill to be moved along the shell 22 toward the workbyi the force of the hammerv piston; The ratchet ring,

shock or jar to.

being connected to the feed nut'through the pin-I;

ion 61; will also rotate in'the same direction as the feed nut and its teeth 54 will merely depress .thepawls 56 astheypass over thefreea' endsof the'pawls. 7 V

Upon reversal of the piston the spiral engagement between it and the bar 42'c'auses the bar to rotate in a directionto bring the ends ofsthe pawls 46 into abutting relationship with the teeth 54 and,in consequencea thrust is impart- 'ed' to the ratchet ring 52 which willcause it to rotate. This movement of the ratchetring'is transmitted through the pinion. 61 to the feed nut 69 which will then berotated furtherv in a clockwise direction to advance it and the rock drill toward the work.

The distance which the rock drill is initially moved forwardly along the shell by the force of the hammer piston 21 at the beginning of its rearward stroke depends, of course, upon the degree of penetration of the working implement into the rock at each blow of the hammer piston but, in any case, the rock drill is moved forwardly, by the jar occasioned by the hammer piston and by the subsequent thrust against the ratchet ring, the distance required to bring the percussive element within the correct striking distance of the working implement. In practice, this final forward movement of the rock drill has been found to be fully accomplished immediately after the beginning of the rearward stroke of the hammer piston.

After the described movement of the feed nut has been effected the rock drill will be definitely restrained against further forward movement by the abutting surfaces of the working implement and the chuck mechanism. In consequence, the feed nut 69 and the parts connected thereto are incapable of further rotary movement. The ratchet ring 52 will, therefore, remain stationary, as will also the bar 42. The piston 21 will then rotate relatively to the bar 42 during the remainder of its stroke and rotate the chuck 33 and the working implement to a new position.

When the piston reverses in the rear end of the piston chamber a jar is, of course, also imparted to the rock drill but this force will be ineffective to shift the rock drill by reason of the engagement of the paw1s56 with the teeth 54. These elements will then prevent reverse movement of the ratchet ring 52 and thus the movement of the feed nut 69 necessary to effect or permit retrograde movement of the rock drill.

The described cycle of operations is repeated until the working implement has penetrated the rock to the limit of its extent and to accomplish which necessarily requires that the rock drill move to the forward extremity of the shell. In order, therefore, to return the rock drill to its initial position the plate 58 is rotated, by means of the lever 63, to a position in which the wings 59 tilt the pawls 56 out of the path of the teeth 54 and release the pawl 51 to enable the latter to move into position for engaging the ratchet teeth.

During the subsequent reciprocations of the hammer piston 21 the jars applied to the rock drill upon reversal of the piston at the end of its rearward stroke cause the feed nut 69 torotate freely on the feed screw 13 and the rock drill will be moved rearwardly towards its initial position and constitute the sole force for retracting the rock drill. The ratchet ring 52 will then also be free to rotate within the back head to permit of this movement of the feed nut but will be held against movement in the opposite direction by the pawl 51 which will be in engagement with or in position to engage a tooth 54. Thus, when the piston 21 reverses in the front end of the piston chamber 25 the jar applied to the rock drill and tending to move it forwardly will be rendered ineffective by the pawl 51. Upon continued operation of the hammer piston 21 the rock drill will be gradually moved rearwardly to the starting position.

I claim:

1. In a rock drilling mechanism, the combination of a rock drill and a guide therefor, a feeding mechanism for moving the rock drill relatively to the guide and comprising a pair of members in threaded engagement with each other, a hammer piston reciprocable in the rock drill applying jars thereto to move the rock drill along the guide, and rotary means actuated by the hammer piston during alternate strokes thereof for rotating one of the members to assist in moving the rock drill in one direction.

2. In a rock drilling mechanism, the combination of a rock drill and a guide therefor, a hammer piston in the rock drill, feeding mechanism for moving the rock drill relatively to the guide, and means actuated by the hammer piston and operating to actuate the feeding mechanism to move the rock drill counter to the direction of movement of the hammer piston.

3. In a rock drilling mechanism; the combination of a rock drill and a guide therefor, a feed screw on the guide, a feed nut in the rock drill in threaded engagement with the feed screw, a hammer piston reciprocable in the rock drill applying jars thereto to move the rock drill along the guide, and means actuated by the hammer piston during alternate strokes thereof for rotating the feed nut to assist in moving the rock drill relatively to the guide.

4. In a rock drilling mechanism, the combination of a rock drill and a guide therefor, feeding mechanism for the rock drill comprising a stationary member and a rotary member in threaded engagement with the stationary member, a ratchet ring rotatable in the rock drill, a driving connection between the ratchet ring and the rotary member, a hammer piston, and means interlocked with the hammer piston to impart rotary movement to the ratchet ring and thus to the rotary member during a stroke of the hammer piston.

5. In a rock drilling mechanism, the combination of a rock drill and a guide therefor, feeding mechanism for the rock drill comprising a stationary member and a rotary member in threaded engagement with the rotary member, a ratchet ring rotatable in the rock drill and being operatively connected with the rotary member to rotate said rotary member, a hammer piston, means for selectively controlling the direction of rotation of the ratchet ring, and means interlocked with the hammer piston to impart rotary movement to the ratchet ring during a portion of the rearward stroke of the hammer piston.

6. In a rock drilling mechanism, the combination of a rock drill and a guide therefor, feeding mechanism for the rock drill comprising a stationary member and a rotary member in threaddrill along the support, a ratchet ring rotatable in the rock drill and being operatively connected tothe rotary member to rotatesaid rotary member, means interlocked tosaid piston to cause said piston to move along a spiral path and to impart rotary movement to the ratchet ring, and means selectively engageable with the ratchet ring to render the jars of the hammer piston non-effective to move the rock drill relatively to the support.

WILLIAM A. MORRISON.

DISCLAIMER 2,124,627.W'illiam A. Morrison, Easton, Pa. ROCK DRILL MECHANISM. Patent dated July 26, 1938. Disclaimer filed September 22, 1939, by the assignee, IngersolZ-Rand Company. Hereby enters this disclaimer to claim 2 in said specification.

[Ofiicial Gazette October 10, 1939.] I 

